This invention relates to a light source unit having a number of flash tubes and, more particularly, to a high brightness light source unit for use in a photographing apparatus using an endoscope.
Generally, it is impossible to make a light guide for an endoscope large in diameter since part of it is required to be inserted into a human body and yet the light entering a light-incident surface of it is limited to one having an angle of incidence which falls within a specified range. It is difficult, therefore, to guide all light generated from one flash tube into the light guide. Conventionally, therefore, it was only possible to guide part of such light into the light guide. In the photographing which is effected using such a light guide, therefore, it was impossible to obtain a sufficient amount of light and so shortage of exposure was very likely to occur.
Accordingly, the object of the invention is to provide a light source unit for the photographing performed with the use of an endoscope, which unit is capable of introducing a sufficient amount of light into a light guide of the endoscope.